Solid Earth Seminars

Coastal Groundwater response to climate variability coupling in California and Portugal

Transmissão através de Videoconferência

Por Kate Malmgren (Universidade do Algarve, Portugal).

Aquifers are a fundamental source of fresh water, yet they are particularly vulnerable in coastal Mediterranean regions due to climate and anthropogenic pressures. Examining the interrelationships between ocean-atmosphere teleconnections and groundwater levels in coastal aquifers of California and Portugal reveal information pertinent to securing future groundwater resources. Piezometric and climate indices (1989-2019) are analyzed using singular spectral analysis (SSA) and wavelet transform methods. SSA identifies signals consistent with the dominant climate patterns. Lower frequency oscillations have a greater influence on hydrologic patterns, with the Pacific Decadal Oscillation (52.75%) and the North Atlantic Oscillation (46.25%) on average accounting for the largest amount of groundwater level variability. Wavelet coherences show non-stationary covariability between climate patterns and groundwater levels in distinct period bands and also show that coupled climate patterns are associated with major drought periods.

Transmissão em direto via Zoom.

IDL - Instituto Dom Luiz